Author

Date of Award

Document Type

Degree Name

Department

First Advisor

Second Advisor

John Chen (Committee Member)

Third Advisor

Daniel Pavuk (Committee Member)

Fourth Advisor

George Bullerjahn (Committee Member)

Fifth Advisor

Jeffrey Johansen (Committee Member)

Abstract

The ecology and adaptations of aerial algal communities from selected areas in North America were examined. First, morphological adaptations to desiccation as well as microhabitat preference of diatoms were explored from the Great Smoky Mountains National Park (GSMNP). Reduced size as an adaptation against desiccation was not supported by the data, with aerial diatoms being longer than had been previously shown in the literature. However, a reduction in the amount of open area on the valve face as an adaptation against desiccation was supported by the data. Second, aerial algal communities from the GSMNP and the Lake Superior region were compared and contrasted. Factors structuring algal communities in each region were examined and similarities and differences were identified between the two regions. These regions were not found to support unique aerial algal communities. Third, bryophyte-algal associations were investigated from a cliff face in O’ahu, HI. Algal species were examined for fidelity to bryophyte species within this site. There was no relationship found between algal species and bryophyte species, however, there was a relationship between algal species and both aspect and light levels. Finally, desiccation tolerance of algal communities was studied through a laboratory experiment. Changes in algal community composition were examined after exposure to different periods of desiccation. Overall, algal community composition was not found to change as a result of exposure to different periods of desiccation. This dissertation explored algal communities from understudied aerial and explored factors that structure and influence community composition.